BUCKINGHAM. — DIVISION OF LABOR AMONG ANTS. 495 



nest, but that they do not go into the field until they have nearly 

 reached their darkest color, and that they do not fight until they have 

 completely attained that condition. It has been stated by Fielde 

 (:03'^, p. 321) that if ants from different colonies, even of different 

 species, are placed together within twelve hours after hatching, and if 

 they touch all the other ants with their antennae during the three days 

 following, they will live together peaceably. She further states (Fielde, 

 :02, p. 541) that before an ant is five days old it has all its reflexes de- 

 termined. The fact that ants when very young do not fight at all 

 would account for the possibility of forming mixed colonies, as just 

 described. Probably by the time their fighting instincts are developed, 

 they have become so used to one another that they have no inclination 

 to fight. The same would probably also be true of ants emerging from 

 the pupal state under similar conditions in out-door colonies. 



6. Some attention was paid to the kinds of activity in which the 

 queens of colonies of various sizes engaged, in order that queens and 

 workers might be compared. While the queens of those species of 

 Camponotus which were studied are capable of bringing up colonies 

 and of doing all the work necessary for this, it was found that in large 

 colonies they commonly serve merely as egg-layers, except possibly in 

 time of danger ; but in small colonies, even in those which are of suffi- 

 cient age to contain workers of all sizes, their instincts occasionally 

 cause them to revert to other occupations, and to share in such activi- 

 ties as building and tending the young. Indeed, Wheeler (: 04% p. 156) 

 found a queen of Colobopsis guarding the entrances of the nest, and 

 says (iOS", p. 45), " So far as I was able to observe, both the virgin and 

 the deiilated females of Leptothorax behaved in all respects like the 

 workers," and, "it should also be noted that in artificial nests consist- 

 ing exclusively of female Myrmicas and Leptothorax colonies, the former 

 behaved in nearly all respects like the workers." In Trachymyrmex 

 septentrionalls he (Wheeler, : 06^ p. 99) saw old, deiilated females doing 

 work, and he also reports (: 07% p. 741) the same fact for Atta {Tra- 

 cliymyrmex) turrifex. McCook ('79, p. 148) states that the queen of 

 Pogonomyrmex probably assists somewhat in the nursing of the young, 

 and may contribute something of her strength to the extension of the 

 formicary bounds. This reversion of the queen to her earlier occupa- 

 tions seems to hold true not only for deiilated individuals, which must 

 work when founding a colony, but also for winged queens. That the 

 work in the case of the latter is due to virgin instincts, seems probable 

 from Wheeler's statements (tOB'^). The deiilated and winged queens 

 do not seem to differ in respect to those activities which were noted. 

 Possibly if I had used some such species as Formica consocians (Wheeler, 



